The objective of the proposed study is to investigate the feasibility of photothermally altering the sebaceous glands and interfering with sebum production while preserving the epidermis. The system used in this study will consist of a compact laser combined with cryogen spray cooling of the epidermis. The laser energy is expected to thermally alter the sebaceous glands whereas the epidermal cooling is expected to protect the epidermis from thermal damage, reducing pain, erythema, edema, and blistering, thus causing minimal morbidity after the treatment. Phase-I studies will consist of photothermal treatment of sebaceous glands in a rabbit ear model, followed by biopsy, histological analysis, and sebum production measurement. Principles of tissue optics and optical and thermal modeling techniques will be used in order to iterate to an appropriate experimental treatment parameter set. The specific aims of the proposed Phase-I study are to demonstrate the following changes after treatment: -alteration of the sebaceous glands and associated structures, -stability of alteration as a function of time, -reduction in sebum production, -epidermal preservation. Successful completion of Phase-I research will spur the construction of an SBIR Phase-II proposal emphasizing the development of a commercially oriented laser system for the treatment for acne vulgaris. PROPOSED COMMERCIAL APPLICATIONS: This research could lead to the development of a significantly improved technique for the treatment of acne. It may allow for an efficient acne treatment with minimal morbidity thereby eliminating the need for years of chronic therapy with expensive and sometimes dangerous pharmaceuticals. If successful, this method would lead to improvement in cosmetic appearance and lower total costs for the patient and society.